A commodity management technique is conventionally used, in which a radio tag is attached to each article, and a tag ID is read by a detector (e.g., Japanese Patent Laid-Open No. 10-198731).
This prior art has described a technique for preparing and managing a database of radio tag IDs but does not consider any technique for combining the radio tag IDs with image information to implement a more advanced function. How to easily acquire and register auxiliary information such as image information in association with tag IDs is not taken into consideration, either.